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Weygandt: Entstehung der Träume, 1893.

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ADDITIONAL BIBLIOGRAPHY

Ackland, Theodore Dyke: Circular letters relating to hours of sleep necessary for schoolboys (particularly in English public schools), 1905.

Alsberg, Moritz: Die protoplasmatische Bewegung der Nervenzellenfortsätze in ihren Beziehungen zum Schlaf. Deutsche Gesellsch. f. Anthrop.

Ethnol. u. Urgeschichte, Correspondenzblatt, vol. xxxii, pp. 2-8, München, 1901.

Anastay, E.: L’origine biologique du Sommeil et de l’hypnose, Archives de Psychol., Paris, 1908, vol. viii, pp. 63-76.